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For the yard and boom we will again start with the rule of thumb outlined in Oughtreds Clinker Plywood Boatbuilding Manual.

The diameter of a solid yard and boom should be 1/60 of the total length. The head of the Tirrik sail will be 327cm so a yard of 350cm seems appropriate.

The foot of the sail is 275cm which roughly translates to 300cm. The diameter for a solid round section of wood should then be 50mm.

The required stiffness for both yard and boom can be achieved with a 50/47mm 6061T6 tube @1.27kg/m.

Net weight of the yard is 3.5m @1.27kg = 4,45kg.

Net weight of the boom is 3m @1.27kg = 3,81kg.